Electrophotographic image forming apparatuses generally include a photoreceptor drum serving as an image bearer and rotary members that rotate around the photoreceptor drum, namely, a cleaning roller, a charging roller, and the like. The image bearer and such rotary members are rotated by a drive force transmitted from a drive source such as a motor.
For example, a structure proposed in JP-2010-139846-A includes a large-diameter gear to drive the image bearer, a motor to drive the large-diameter gear, and a drive gear to drive a rotary member of a development device, and the drive gear engages an output gear (a prime gear) of the motor, thereby rotating the rotary member.
In this structure, a drive force output from the output gear is transmitted to the image bearer and the rotary member through separate transmission routes. Accordingly, drive connections to transmit the drive force to the rotary members can increase in number, occupying a larger space inside the apparatus.